Details for Benchmark: JZ0994
N 39° 20.533 W 084° 33.567 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- In BUTLER county, OH View Original Datasheet
- H 144
- Marker Type:
- bench mark disk
- massive structures
- Probably hold position/elevation well.
Benchmarks may be on private property or in dangerous locations. Obey local laws. By using the services on Geocaching.com you agree to this disclaimer.
Documented History (by the NGS)
|01/01/1947 by CGS (MONUMENTED)
|DESCRIBED BY COAST AND GEODETIC SURVEY 1947
AT SYMMES. AT SYMMES, ALONG U.S. HIGHWAY 127, SET IN THE TOP OF THE NORTHEAST WING WALL OF A 50-FOOT CONCRETE BRIDGE OVER PLEASANT RUN CREEK, 22 FEET EAST OF THE CENTER LINE OF THE HIGHWAY, 1 FOOT EAST OF THE CONCRETE BANISTER AND ABOUT 1 FOOT ABOVE THE HIGHWAY.
|01/01/1977 by DOD (GOOD)
|RECOVERY NOTE BY US DEPARTMENT OF DEFENSE 1977
RECOVERED IN GOOD CONDITION.
- The horizontal coordinates were scaled from a topographic map and have an estimated accuracy of +/- 6 seconds.
- The orthometric height was determined by differential leveling and adjusted by the National Geodetic Survey in June 1991.
- The geoid height was determined by GEOID99.
- The dynamic height is computed by dividing the NAVD 88 geopotential number by the normal gravity value computed on the Geodetic Reference System of 1980 (GRS 80) ellipsoid at 45 degrees latitude (g = 980.6199 gals.).
- The modeled gravity was interpolated from observed gravity values.